@@ -413,6 +413,8 @@ struct kvm_trace_rec {
#define KVM_CAP_DEVICE_MSIX 28
#endif
#define KVM_CAP_ASSIGN_DEV_IRQ 29
+/* Another bug in KVM_SET_USER_MEMORY_REGION fixed: */
+#define KVM_CAP_JOIN_MEMORY_REGIONS_WORKS 30
#ifdef KVM_CAP_IRQ_ROUTING
@@ -1117,7 +1117,7 @@ int __kvm_set_memory_region(struct kvm *kvm,
for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
struct kvm_memory_slot *s = &kvm->memslots[i];
- if (s == memslot)
+ if (s == memslot || !s->npages)
continue;
if (!((base_gfn + npages <= s->base_gfn) ||
(base_gfn >= s->base_gfn + s->npages)))
@@ -2262,6 +2262,7 @@ static long kvm_dev_ioctl_check_extension_generic(long arg)
switch (arg) {
case KVM_CAP_USER_MEMORY:
case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
+ case KVM_CAP_JOIN_MEMORY_REGIONS_WORKS:
return 1;
#ifdef CONFIG_HAVE_KVM_IRQCHIP
case KVM_CAP_IRQ_ROUTING:
When checking for overlapping slots on registration of a new one, kvm currently also considers zero-length (ie. deleted) slots and rejects requests incorrectly. This finally denies user space from joining slots. Fix the check by skipping deleted slots and advertise this via a KVM_CAP_JOIN_MEMORY_REGIONS_WORKS. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> --- include/linux/kvm.h | 2 ++ virt/kvm/kvm_main.c | 3 ++- 2 files changed, 4 insertions(+), 1 deletions(-)